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arXiv · cond-mat/0208391

Commensurate-incommensurate transition of cold atoms in an optical lattice

H. P. Büchler·G. Blatter·W. Zwerger
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Abstract

An atomic gas subject to a commensurate periodic potential generated by an optical lattice undergoes a superfluid--Mott insulator transition. Confining a strongly interacting gas to one dimension generates an instability where an arbitrary weak potential is sufficient to pin the atoms into the Mott state; here, we derive the corresponding phase diagram. The commensurate pinned state may be detected via its finite excitation gap and the Bragg peaks in the static structure factor.

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H. P. Büchler, G. Blatter, W. Zwerger. 2002-08-20. Commensurate-incommensurate transition of cold atoms in an optical lattice. https://doi.org/10.1103/physrevlett.90.130401

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